He said that his brother was being held as a bargaining chip to try and win the release of Hamas prisoners held by Israel.

"A man with special needs is being held hostage," Mengistu said in Hebrew. "How cruel."

Israel does not allow its citizens to enter Gaza, partly over fears that they may be used as leverage to demand concessions.

Two Israeli soldiers, Oron Shaul and Hadar Goldin, are believed to have been killed in the 2014 war in Gaza and their remains held by Hamas.

The movement has suggested it is willing to trade the bodies in a deal similar to the 2011 swap that saw Israeli soldier Gilad Shalit freed in exchange for more than 1,000 Palestinians in Israeli prisons.

Around 6,500 Palestinians are currently in Israeli jails, according to the Palestinian Prisoners' Club.